Condensed Consolidating Financial Information (Details 4) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Consolidating Statements Of Cash Flows
Net cash provided by (used for) operating activities	$ 856,556	$ 1,781,911	$ 1,418,223
Cash flows from investing activities:
Purchases of investments	(9)	(319)
Sales and maturities of investments	961	23,992	164,510
Cash paid for acquisition of businesses, net	(80,187)	(72,534)	(116,971)
Investments in unconsolidated affiliates	(445)	(2,365)	(5,967)
Capital expenditures	(867,106)	(1,821,315)	(1,178,205)
Proceeds from sales of assets and insurance claims	68,206	156,761	308,538
Proceeds from merger transaction	650,050
Other Changes in Investing	1,081	(1,879)	(13)
Proceeds from sales of unconsolidated affiliate		750	12,640
Net cash used for investing activities	(227,449)	(1,716,909)	(815,468)
Cash flows from financing activities:
Increase (decrease) in cash overdrafts	645	(6,151)	(4,421)
Debt issuance costs	(1,847)		(4,500)
Reduction in revolving credit facilities	(450,000)	(230,932)	(720,000)
Proceeds from (payments for) issuance of common shares	1,296	30,263	5,383
Repurchase of common shares	(99,598)	(250,037)
Reduction in long term debt	(27,478)		(994,181)
Dividends to shareholders	(69,363)	(59,145)	(47,168)
Proceeds from (payments for) commercial paper, net	(525,119)	203,275	329,844
Payments on term loan facility	(300,000)
Cash proceeds from noncontrolling Interest	3,972
Proceeds (issuance) of intercompany debt	625,000
Proceeds from long term debt			698,753
Proceeds from Issuance of Long-term Debt			698,753
Redemption of subsidiary Preferred Shares		(70,875)
Proceeds from revolving credit facilities		465,000
Treasury stock transactions, net	(99,598)	(250,037)
Other	(7,449)	(11,550)	6,704
Net cash (used for) provided by financing activities	(849,941)	69,848	(729,586)
Effect of exchange rate changes on cash and cash equivalents	(25,785)	(23,616)	(8,176)
Net increase (decrease) in cash and cash equivalents	(246,619)	111,234	(135,007)
Cash and cash equivalents, beginning of period	501,149	389,915	524,922
Cash and cash equivalents, end of period	254,530	501,149	389,915
Reportable Legal Entities | Parent Company
Condensed Consolidating Statements Of Cash Flows
Net cash provided by (used for) operating activities	39,478	26,943	16,746
Cash flows from investing activities:
Proceeds from merger transaction	5,500
Cash paid for investments in consolidated affiliates			(100)
Net cash used for investing activities	5,500		(100)
Cash flows from financing activities:
Proceeds from (payments for) issuance of common shares	1,296	30,263	37,455
Dividends to shareholders	(79,304)	(65,450)	(51,713)
Proceeds from term loan	67,500	55,000
Paydown of intercompany debt	(27,000)	(55,000)
Proceeds from (payments for) issuance of parent common shares to affiliates		16,424
Other	(7,767)	(7,740)	(3,296)
Net cash (used for) provided by financing activities	(45,275)	(26,503)	(17,554)
Net increase (decrease) in cash and cash equivalents	(297)	440	(908)
Cash and cash equivalents, beginning of period	1,170	730	1,639
Cash and cash equivalents, end of period	873	1,170	730
Reportable Legal Entities | Guarantor Subsidiaries
Condensed Consolidating Statements Of Cash Flows
Net cash provided by (used for) operating activities	(217,685)	(71,982)	(157,952)
Cash flows from investing activities:
Proceeds from merger transaction	646,078
Changes in intercompany balances	135,518	(418,315)	748,537
Cash paid for investments in consolidated affiliates			(772,000)
Net cash used for investing activities	781,596	(418,315)	(23,463)
Cash flows from financing activities:
Debt issuance costs	(1,847)		(4,500)
Reduction in revolving credit facilities	(450,000)	(170,000)	(720,000)
Reduction in long term debt			(994,112)
Proceeds from (payments for) commercial paper, net	(525,119)	203,275	329,844
Proceeds from term loan	88,058
Payments on term loan facility	(300,000)
Proceeds (issuance) of intercompany debt	625,000
Proceeds from long term debt			698,434
Proceeds from Issuance of Long-term Debt			698,434
Proceeds from revolving credit facilities		450,000
Proceeds from issuance of Parent common shares			772,000
Net cash (used for) provided by financing activities	(563,908)	483,275	81,666
Net increase (decrease) in cash and cash equivalents	3	(7,022)	(99,749)
Cash and cash equivalents, beginning of period	7	7,029	106,778
Cash and cash equivalents, end of period	10	7	7,029
Reportable Legal Entities | Other Subsidiaries (Non-Guarantors)
Condensed Consolidating Statements Of Cash Flows
Net cash provided by (used for) operating activities	1,066,026	1,816,831	1,531,902
Cash flows from investing activities:
Purchases of investments	(9)	(319)
Sales and maturities of investments	961	23,992	164,510
Cash paid for acquisition of businesses, net	(80,187)	(72,534)	(116,971)
Investments in unconsolidated affiliates	(445)	(2,365)	(5,967)
Capital expenditures	(867,106)	(1,821,315)	(1,178,205)
Proceeds from sales of assets and insurance claims	68,206	156,761	308,538
Proceeds from merger transaction	(1,528)
Changes in intercompany balances	(135,518)	418,315	(748,537)
Other Changes in Investing	1,081	(1,879)	(13)
Proceeds from sales of unconsolidated affiliate		750	12,640
Cash paid for investments in consolidated affiliates			(1,544,000)
Net cash used for investing activities	(1,014,545)	(1,298,594)	(3,108,005)
Cash flows from financing activities:
Increase (decrease) in cash overdrafts	645	(6,151)	(4,421)
Reduction in revolving credit facilities		(60,932)
Repurchase of common shares	(99,598)	(250,037)
Reduction in long term debt	(27,478)		(69)
Proceeds from term loan	(155,558)	(55,000)
Cash proceeds from noncontrolling Interest	3,972
Paydown of intercompany debt	27,000	55,000
Payments on parent (Equity or N/P)	(21,322)
Proceeds from long term debt			319
Proceeds from Issuance of Long-term Debt			319
Redemption of subsidiary Preferred Shares		(70,875)
Proceeds from revolving credit facilities		15,000
Treasury stock transactions, net	(99,598)	(250,037)
Proceeds from issuance of Parent common shares			1,544,100
Other	318	(3,810)	10,000
Net cash (used for) provided by financing activities	(272,021)	(376,805)	1,549,929
Effect of exchange rate changes on cash and cash equivalents	(25,785)	(23,616)	(8,176)
Net increase (decrease) in cash and cash equivalents	(246,325)	117,816	(34,350)
Cash and cash equivalents, beginning of period	499,972	382,156	416,505
Cash and cash equivalents, end of period	253,647	499,972	382,156
Consolidating Adjustments
Condensed Consolidating Statements Of Cash Flows
Net cash provided by (used for) operating activities	(31,263)	10,119	27,527
Cash flows from investing activities:
Cash paid for investments in consolidated affiliates			2,316,100
Net cash used for investing activities			2,316,100
Cash flows from financing activities:
Proceeds from (payments for) issuance of common shares			(32,072)
Dividends to shareholders	9,941	6,305	4,545
Payments on parent (Equity or N/P)	21,322
Proceeds from (payments for) issuance of parent common shares to affiliates		(16,424)
Proceeds from issuance of Parent common shares			(2,316,100)
Net cash (used for) provided by financing activities	$ 31,263	$ (10,119)	$ (2,343,627)